单级模块化多电平矩阵变换器支路间电容电压平衡
Voltage balancing in a 1-level modular multilevel matrix converter

模块化多电平矩阵变换器（MMMC）能实现三相交流系统到三相交流系统的能量变换，具有可四象限运行、系统模块化以及良好的低频特性等优点，可直接应用于高压大容量变频调速系统。传统MMMC由于不含支路空心电感，与带支路电感MMMC相比能减小系统的体积与重量，该文针对单级传统MMMC支路电容电压，基于开关次数最优的导通支路选择策略，数值仿真分析了MMMC拓扑H桥支路电容电压的波动，在此基础上提出MMMC拓扑H桥支路间电容电压平衡策略。该策略减小了H桥支路电容电压的波动，通过实验样机验证了该策略的可行性。
Abstract：A modular multilevel matrix converter (MMMC) can convert three phase AC input to three phase AC output. The converters use four-quadrant operation with good modularity and low frequency performance for high-voltage high-power variable frequency drive systems. MMMC designs include the topology without branch inductors and the topology with branch inductor. The MMMC without branch inductors are smaller and lighter.This paper describes a 1-level MMMC with the voltage of the H-bridge branches calculated numerically. The switching times are optimized to balance the voltages in the H-bridge branches. Tests show the effectiveness of the voltage balancing strategy.